Female orca «adopts» cub of another species: «Never seen before»- Corriere.it

A unique case, never observed before in nature. Off the coast of Iceland, researchers saw a female orca with a baby swimming alongside her. Nothing unusual, it normally happens among cetaceans. Except that the puppy was definitely not his, but it was even of another species: a pilot whale (Globicephala melas), also known as a pilot whale.

The adoption

Cases of «adoption» from parts of mothers of puppies belonging to other species are known, for example female dogs giving milk to kittens, even among cetacean species, but it had never been noticed among orcas. The observation took place in August 2021 near Snæfellsnes in western Iceland. The case is so unique that a scientific study has been published on Canadian Journal of Zoology
also because the the only interactions between the two species concern the predation of orcas on pilot whales. Groups of killer whales, highly social animals, have a matrilineal organization: in fact, they are led by a matriarch followed by sisters, daughters and granddaughters with their young and only one adult male. Even pilot whales, however, have a similar social organization.

Malnutrition

The female orca, already known by the researchers and called Sædis ( SN0540), was noticed several times while she was swimming alongside a young pilot whale alongside two other orcas: the adult female Dragonfly (SN0092) and the adult male Zale (SN0089 ). The puppy, the Orcaguardians researchers found, did not appear to be in good health. He had it clear signs of malnutritionthe fetal folds typical of cetaceans indicated that he had not been born for a long time.

Adoption or kidnapping

Scientists are still uncertain about the case: it could be an adoption of an orphaned or abandoned pilot whale pup. But nor do they exclude the idea of ​​Sædis’s “abduction” of the infant, who had never given birth in the previous nine years that she had been noticed and followed up. It is therefore unlikely that she could have had milk to feed the young, but she could have had a birth just prior to the pilot whale adoption, with her pup having died or been lost.